linux/drivers/gpio/gpio-sodaville.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 *  GPIO interface for Intel Sodaville SoCs.
   4 *
   5 *  Copyright (c) 2010, 2011 Intel Corporation
   6 *
   7 *  Author: Hans J. Koch <hjk@linutronix.de>
   8 */
   9
  10#include <linux/errno.h>
  11#include <linux/gpio/driver.h>
  12#include <linux/init.h>
  13#include <linux/interrupt.h>
  14#include <linux/io.h>
  15#include <linux/irq.h>
  16#include <linux/kernel.h>
  17#include <linux/of_irq.h>
  18#include <linux/pci.h>
  19#include <linux/platform_device.h>
  20
  21#define DRV_NAME                "sdv_gpio"
  22#define SDV_NUM_PUB_GPIOS       12
  23#define PCI_DEVICE_ID_SDV_GPIO  0x2e67
  24#define GPIO_BAR                0
  25
  26#define GPOUTR          0x00
  27#define GPOER           0x04
  28#define GPINR           0x08
  29
  30#define GPSTR           0x0c
  31#define GPIT1R0         0x10
  32#define GPIO_INT        0x14
  33#define GPIT1R1         0x18
  34
  35#define GPMUXCTL        0x1c
  36
  37struct sdv_gpio_chip_data {
  38        int irq_base;
  39        void __iomem *gpio_pub_base;
  40        struct irq_domain *id;
  41        struct irq_chip_generic *gc;
  42        struct gpio_chip chip;
  43};
  44
  45static int sdv_gpio_pub_set_type(struct irq_data *d, unsigned int type)
  46{
  47        struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
  48        struct sdv_gpio_chip_data *sd = gc->private;
  49        void __iomem *type_reg;
  50        u32 reg;
  51
  52        if (d->hwirq < 8)
  53                type_reg = sd->gpio_pub_base + GPIT1R0;
  54        else
  55                type_reg = sd->gpio_pub_base + GPIT1R1;
  56
  57        reg = readl(type_reg);
  58
  59        switch (type) {
  60        case IRQ_TYPE_LEVEL_HIGH:
  61                reg &= ~BIT(4 * (d->hwirq % 8));
  62                break;
  63
  64        case IRQ_TYPE_LEVEL_LOW:
  65                reg |= BIT(4 * (d->hwirq % 8));
  66                break;
  67
  68        default:
  69                return -EINVAL;
  70        }
  71
  72        writel(reg, type_reg);
  73        return 0;
  74}
  75
  76static irqreturn_t sdv_gpio_pub_irq_handler(int irq, void *data)
  77{
  78        struct sdv_gpio_chip_data *sd = data;
  79        unsigned long irq_stat = readl(sd->gpio_pub_base + GPSTR);
  80        int irq_bit;
  81
  82        irq_stat &= readl(sd->gpio_pub_base + GPIO_INT);
  83        if (!irq_stat)
  84                return IRQ_NONE;
  85
  86        for_each_set_bit(irq_bit, &irq_stat, 32)
  87                generic_handle_domain_irq(sd->id, irq_bit);
  88
  89        return IRQ_HANDLED;
  90}
  91
  92static int sdv_xlate(struct irq_domain *h, struct device_node *node,
  93                const u32 *intspec, u32 intsize, irq_hw_number_t *out_hwirq,
  94                u32 *out_type)
  95{
  96        u32 line, type;
  97
  98        if (node != irq_domain_get_of_node(h))
  99                return -EINVAL;
 100
 101        if (intsize < 2)
 102                return -EINVAL;
 103
 104        line = *intspec;
 105        *out_hwirq = line;
 106
 107        intspec++;
 108        type = *intspec;
 109
 110        switch (type) {
 111        case IRQ_TYPE_LEVEL_LOW:
 112        case IRQ_TYPE_LEVEL_HIGH:
 113                *out_type = type;
 114                break;
 115        default:
 116                return -EINVAL;
 117        }
 118        return 0;
 119}
 120
 121static const struct irq_domain_ops irq_domain_sdv_ops = {
 122        .xlate = sdv_xlate,
 123};
 124
 125static int sdv_register_irqsupport(struct sdv_gpio_chip_data *sd,
 126                struct pci_dev *pdev)
 127{
 128        struct irq_chip_type *ct;
 129        int ret;
 130
 131        sd->irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0,
 132                                            SDV_NUM_PUB_GPIOS, -1);
 133        if (sd->irq_base < 0)
 134                return sd->irq_base;
 135
 136        /* mask + ACK all interrupt sources */
 137        writel(0, sd->gpio_pub_base + GPIO_INT);
 138        writel((1 << 11) - 1, sd->gpio_pub_base + GPSTR);
 139
 140        ret = devm_request_irq(&pdev->dev, pdev->irq,
 141                               sdv_gpio_pub_irq_handler, IRQF_SHARED,
 142                               "sdv_gpio", sd);
 143        if (ret)
 144                return ret;
 145
 146        /*
 147         * This gpio irq controller latches level irqs. Testing shows that if
 148         * we unmask & ACK the IRQ before the source of the interrupt is gone
 149         * then the interrupt is active again.
 150         */
 151        sd->gc = devm_irq_alloc_generic_chip(&pdev->dev, "sdv-gpio", 1,
 152                                             sd->irq_base,
 153                                             sd->gpio_pub_base,
 154                                             handle_fasteoi_irq);
 155        if (!sd->gc)
 156                return -ENOMEM;
 157
 158        sd->gc->private = sd;
 159        ct = sd->gc->chip_types;
 160        ct->type = IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW;
 161        ct->regs.eoi = GPSTR;
 162        ct->regs.mask = GPIO_INT;
 163        ct->chip.irq_mask = irq_gc_mask_clr_bit;
 164        ct->chip.irq_unmask = irq_gc_mask_set_bit;
 165        ct->chip.irq_eoi = irq_gc_eoi;
 166        ct->chip.irq_set_type = sdv_gpio_pub_set_type;
 167
 168        irq_setup_generic_chip(sd->gc, IRQ_MSK(SDV_NUM_PUB_GPIOS),
 169                        IRQ_GC_INIT_MASK_CACHE, IRQ_NOREQUEST,
 170                        IRQ_LEVEL | IRQ_NOPROBE);
 171
 172        sd->id = irq_domain_add_legacy(pdev->dev.of_node, SDV_NUM_PUB_GPIOS,
 173                                sd->irq_base, 0, &irq_domain_sdv_ops, sd);
 174        if (!sd->id)
 175                return -ENODEV;
 176
 177        return 0;
 178}
 179
 180static int sdv_gpio_probe(struct pci_dev *pdev,
 181                                        const struct pci_device_id *pci_id)
 182{
 183        struct sdv_gpio_chip_data *sd;
 184        int ret;
 185        u32 mux_val;
 186
 187        sd = devm_kzalloc(&pdev->dev, sizeof(*sd), GFP_KERNEL);
 188        if (!sd)
 189                return -ENOMEM;
 190
 191        ret = pcim_enable_device(pdev);
 192        if (ret) {
 193                dev_err(&pdev->dev, "can't enable device.\n");
 194                return ret;
 195        }
 196
 197        ret = pcim_iomap_regions(pdev, 1 << GPIO_BAR, DRV_NAME);
 198        if (ret) {
 199                dev_err(&pdev->dev, "can't alloc PCI BAR #%d\n", GPIO_BAR);
 200                return ret;
 201        }
 202
 203        sd->gpio_pub_base = pcim_iomap_table(pdev)[GPIO_BAR];
 204
 205        ret = of_property_read_u32(pdev->dev.of_node, "intel,muxctl", &mux_val);
 206        if (!ret)
 207                writel(mux_val, sd->gpio_pub_base + GPMUXCTL);
 208
 209        ret = bgpio_init(&sd->chip, &pdev->dev, 4,
 210                        sd->gpio_pub_base + GPINR, sd->gpio_pub_base + GPOUTR,
 211                        NULL, sd->gpio_pub_base + GPOER, NULL, 0);
 212        if (ret)
 213                return ret;
 214
 215        sd->chip.ngpio = SDV_NUM_PUB_GPIOS;
 216
 217        ret = devm_gpiochip_add_data(&pdev->dev, &sd->chip, sd);
 218        if (ret < 0) {
 219                dev_err(&pdev->dev, "gpiochip_add() failed.\n");
 220                return ret;
 221        }
 222
 223        ret = sdv_register_irqsupport(sd, pdev);
 224        if (ret)
 225                return ret;
 226
 227        pci_set_drvdata(pdev, sd);
 228        dev_info(&pdev->dev, "Sodaville GPIO driver registered.\n");
 229        return 0;
 230}
 231
 232static const struct pci_device_id sdv_gpio_pci_ids[] = {
 233        { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_SDV_GPIO) },
 234        { 0, },
 235};
 236
 237static struct pci_driver sdv_gpio_driver = {
 238        .driver = {
 239                .suppress_bind_attrs = true,
 240        },
 241        .name = DRV_NAME,
 242        .id_table = sdv_gpio_pci_ids,
 243        .probe = sdv_gpio_probe,
 244};
 245builtin_pci_driver(sdv_gpio_driver);
 246